1. Field of the Invention
The present invention pertains to the identification of user-selectable regions. More particularly, this invention relates to identifying user-selectable regions within a sequence of display frames.
2. Background
Computer technology is continually advancing, providing newer and newer systems, each more powerful than the previous. These high-performance computer systems are finding expanded uses in a wide range of personal, business and academic fields. One such use of high-performance computer technology is in the area of multimedia. Multimedia refers to providing information to system users via multiple mediums concurrently. For example, multimedia may include concurrent presentation of video, audio and textual information. In addition, many multimedia systems provide for user-interaction, which allows system users to interact with the information being presented to them.
One disadvantage to multimedia systems, however, is the large amount of data necessary to generate the presentation. For example, a typical multimedia movie displayed by a computer system is displayed at a rate of 30 frames per second (fps). Each frame within the movie can require up to 1.2 megabytes of storage space for a 640.times.480 resolution display device utilizing 32 bits of color. Thus, a 60-second movie requires 1800 frames, or up to 2.16 gigabytes of video data. In addition, storage space is also required for any audio, textual, etc. data being presented concurrently with the video data, as well as storage space for any other control information for the movie. Thus, it would be beneficial to provide a system which reduces the amount of data necessary to display a multimedia movie.
One type of user-interaction currently supported in many non-multimedia applications is referred to as a "hot spot" or "hot button". A hot button is a region identified on the display device as being selectable by the user. For example, a hot button may be a rectangular-shaped region on the screen with the word "help" in the middle. By moving a pointing device over the hot button with a mouse and depressing a mouse button, the help hot button is selected by the user. Upon receipt of this input, the computing system responds by displaying, for example, an index screen identifying subject headings for which help is available.
The control information required to support hot buttons in a multimedia movie requires additional storage space within the computer system. Typically, programs using hot buttons store the data for the hot button in the computer system for each display frame containing the button. However, due to the storage requirements of the video and other multimedia presentation data, it would be beneficial to provide a memory-efficient manner in which to store the necessary control information for hot buttons in multimedia movies.
Furthermore, user-interaction typically supports multiple user options concurrently. For example, both a "help" hot button and a "preferences" hot button may be displayed to the system user. The system's response is thus dependent on which hot button, if any, is activated by the system user. Thus, it would be beneficial to provide a system which could display multiple user-selectable regions in a multimedia movie concurrently and accurately distinguish between regions to determine which region is selected.
Additionally, it would be advantageous to allow a particular hot button to cause different responses by the computer system at different points in time. For example, the help index displayed to the user upon activating the help hot button may be different depending on when the user selects the hot button. The information to be displayed by the computer system may change any number of times during the presentation of the video information, up to and including multiple changes for each frame. Typically, these changes are supported in the system by storing a separate help hot button for each frame in which the button occurs. Storing such separate information, however, requires significant additional storage for the movie. Thus, it would be beneficial to provide an efficient manner in which to keep track of which of several actions should be taken by the system upon selection of a hot button.
The present invention provides for these and other advantageous results.